In the treatment of fracture, how to carry out reduction and fixation according to bone structures is a very important factor, which will directly influence on the process and quality of fracture union, and is critical to the success of the operation. In view of anatomy, a bone mainly composes of a periosteum, a cortical bone, a cancellous bone, and so on. The cortical bone is compact and solid, has strong compression resistance, and located at outside. The cancellous bone is located inside the bone, is consisted of structure tissues, such as bone trabeculae, interwoven into a network, and has a loose structure. The bone trabeculae are mostly arranged in a direction consistent with a direction of stress which the bone is withstood. At different parts, the bone trabeculue are extended in different directions. The bone trabeculae in the proximal femur may be classified into primary tensile trabeculae, secondary tensile trabeculae, primary compressive trabeculae and secondary compressive trabeculae. For bones of a human body, according to the rule during the union and remodeling of the fractured bone, if displacement occurred after fracture, callus will be significantly formed at the compression side, and the bone trabeculae therein will be arranged in a direction in which compression stress is transferred, while at the tension side, absorption of bone will occurred and the structure of the bone trabeculae becomes loose.
After a conventional fracture internal fixation device is implanted, the bone trabeculae at broken ends will be destroyed due to the occupying effect of the implanted device, the growth and recovery to its continuity of the bone trabeculae at the broken ends will be influenced, and callus inside and outside of a bone marrow will not grow in balance way, especially for the aged people who suffers from osteoporotic fracture, it is possible that after the cortex of the bone is healed, the cancellous bone is still poorly healed, and the cancellous bone in the medullary cavity may not be fully recovered to its continuity, it will influence transmission of normal load and is likely to cause stress concentration, will also influence the overall strength of the healed bone, and sometimes, it is possible to result in delayed union or nonunion.
With the continuously development of the internal fixation technology of the orthopedics, it is really necessary to design a new fixation device enabling the cortex of the fractured bone and the primary bone trabeculae to be remolded at the same time so that the fracture may be healed both inside and outside of the marrow at the same time, by guiding the treatment of the fracture under the principle of the biology and the biomechanics. Whereby, the healing rate of the fracture may be speeded up, the healing quality and strength of the fracture may be improved, and the rate of occurrence of complications, such as fracture nonunion, delay union, loose or rupture of the internal fixation device, and so on may be lowered down.
The foresaid information as disclosed in the background part only serves to enhance understanding of the background of the disclosure, thereby it may not contain ordinary skill information that has been well known.